Effect
+25/30/35/40/45//50/60% Extra Storm Cloud damage
What Lightning Stone does
Lightning Stone is a rare-rarity artifact in Sephiria. In the inventory grid it occupies its own space, and any tablets you place beside it multiply the effect shown above.
It counts toward the Storm Cloud combo — pair it with other artifacts tagged Storm Cloud to trigger that combo's set bonus during a run.
Data source
Effect text and rarity are taken verbatim from TEAM HORAY's Fan Kit catalog (game build 1.0.25, indexed 2026-08-11), reproduced for reference. We do not add inferred numbers or unlock conditions that the Fan Kit does not supply.